Change in Roof Pitch Along a Single Wall

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I'd like to do a hip roof with pitch changes along a single exterior wall.  Can this be done without manual roof edits (using wall directives, or roof baseline polylines, or some other technique I don't know of)?


I've attached an example image of what it should look like.  The ceilings are the same (9') throughout.  The low roof is 9 over 12 and the higher part has a 9 over 12 skirt around the edges to match, then changes to 16 over 12 starting 0.5" from the baseline.  As you can see, the 16 over 12 section has 4 main roof planes (plus the skirt) but the 9 over 12 section intersects the higher section and has only 3 planes.


I've tried making this in 4 different ways and the last two ways almost work.


1) If you try to simply split the long exterior walls in half and give different pitch directives, the auto roof chooses one of the two pitches and ignores the other, so this doesn't work.


2) If you make two roof groups using a room divider, you end up with two entirely separate roofs (two points; the lower hip roof isn't joined to the higher roof because it's in a separate group).


3) If you make two roof groups as above and make roof baseline polylines, you can change the interior pitches and cause the lower roof to intersect by overlapping the interior portion of the roof baseline polylines.  Set the 9 over 12 section to "against wall" and the high section to 9/12 and 16/12 to match the exterior walls, and manually intersect them by moving the "against wall" baseline into the higher roof.  This works except the lower roof extends into the attic of the higher roof which isn't ideal since I'd like to visualize the attic space properly.


4) If you manually create two separate baseline polylines in the same group via copy/paste, you can set the separate roof directives as above, but since they're in the same roof group, if the outer lines are flush, a single pitch is chosen for the wall again (just as in case 1).  If you separate the baseline polyline edges by a fraction of an inch along the exterior wall it creates separate planes as intended, but it creates a discontinuity along the eaves that you can see in the 3D view (pictured) and it causes the shingles over the 16/12 hip to extend all the way down whereas they should stop around 0.5" from the baseline.



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I'm sure that if someone reads this and knows the answer, they will respond with that answer.


I don't know, and don't care enough to spend the time required to try and find the answer.


Have you sent this question in to support?



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The most likely, possible answer is that if the ceiling heights are different, one space to the other in your posted image, setting those actual heights would produce what you wish automatically but I am just guessing because you have not shown us what you outcome should look like in an elevation view. Are the ceiling heights different?



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No, the ceiling height and wall height doesn’t change. The eaves, fascia and soffit are at the same height in the two sections and continue seamlessly where the roof changes. This seems to be the purpose of having the 9/12 “skirt” at the bottom of the 12/12 section. It means all the eaves are formed from 9/12 roofing and can connect seamlessly.

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